EFFECTS OF SUBSTRATE DEFORMABILITY ON CELL BEHAVIORS: ELASTIC MODULUS VERSUS THICKNESS

2017 ◽  
Vol 17 (05) ◽  
pp. 1750088 ◽  
Author(s):  
ZAHRA GOLI-MALEKABADI ◽  
MOHAMMAD TAFAZZOLI-SHADPOUR ◽  
EHSAN SEYEDJAFARI
Keyword(s):  
Cell Proliferation ◽  
Elastic Modulus ◽  
Umbilical Vein ◽  
Cell Behavior ◽  
Substrate Thickness ◽  
Microfluidic Chips ◽  
Cell Behaviors ◽  
Varying Thickness ◽  
Wide Range ◽  
Umbilical Vein Endothelial Cells

The deformability of the substrate stimulating cell mechanotransduction depends not only on elastic modulus but also on the thickness. Polydimethylsiloxane (PDMS) which is widely used in microfluidic chips and platforms can be fabricated in a wide range of elastic modulus and thickness. In this study, we cultured human umbilical vein endothelial cells (HUVECs) on four groups of PDMS substrates of varying thickness and elastic modulus to examine effects of these parameters on morphology, viability and proliferation of cells. Both elastic modulus and thickness affected cell behavior. In general, the thickness of substrates had relatively higher impact on endothelial morphology than elastic modulus. Elongation of HUVECs on thick substrates was more intense compared to those on thin substrates. Both lowering thickness and reducing elastic modulus of PDMS decreased the viability of HUVECs, although thickness was more influential. Decrease in substrate thickness reduced cell proliferation regardless of substrate elastic modulus. In conclusion, our results suggest that endothelial behavior depends on substrate deformability, but cells react differently to the elastic modulus and thickness of PDMS by morphology, viability and growth. Results can improve the comprehension of cell mechanotransduction.

scholarly journals RNA-Seq Data-Mining Allows the Discovery of Two Long Non-Coding RNA Biomarkers of Viral Infection in Humans

2020 ◽  
Vol 21 (8) ◽  
pp. 2748 ◽  
Author(s):  
Ruth Barral-Arca ◽  
Alberto Gómez-Carballa ◽  
Miriam Cebey-López ◽  
María José Currás-Tuala ◽  
Sara Pischedda ◽  
...  
Keyword(s):  
Gene Expression ◽  
Viral Infections ◽  
Umbilical Vein ◽  
Cell Types ◽  
Dermal Fibroblasts ◽  
Learning Approaches ◽  
Rna Seq ◽  
Wide Range ◽  
Healthy Control ◽  
Umbilical Vein Endothelial Cells

There is a growing interest in unraveling gene expression mechanisms leading to viral host invasion and infection progression. Current findings reveal that long non-coding RNAs (lncRNAs) are implicated in the regulation of the immune system by influencing gene expression through a wide range of mechanisms. By mining whole-transcriptome shotgun sequencing (RNA-seq) data using machine learning approaches, we detected two lncRNAs (ENSG00000254680 and ENSG00000273149) that are downregulated in a wide range of viral infections and different cell types, including blood monocluclear cells, umbilical vein endothelial cells, and dermal fibroblasts. The efficiency of these two lncRNAs was positively validated in different viral phenotypic scenarios. These two lncRNAs showed a strong downregulation in virus-infected patients when compared to healthy control transcriptomes, indicating that these biomarkers are promising targets for infection diagnosis. To the best of our knowledge, this is the very first study using host lncRNAs biomarkers for the diagnosis of human viral infections.

Evolocumab, a proprotein convertase subtilisin/kexin type 9 inhibitor, promotes angiogenesis in vitro

2019 ◽  
Vol 97 (5) ◽  
pp. 352-358 ◽  
Author(s):  
Leila Safaeian ◽  
Golnaz Vaseghi ◽  
Hedieh Jabari ◽  
Nasim Dana
Keyword(s):  
Cell Proliferation ◽  
Umbilical Vein ◽  
Tube Formation ◽  
Enzyme Linked Immunosorbent Assay ◽  
Proprotein Convertase ◽  
Physiological Processes ◽  
And Migration ◽  
Umbilical Vein Endothelial Cells ◽  
Endothelial Growth Factor

The proprotein convertases family is involved in several physiological processes such as cell growth, migration, and angiogenesis, and also in different pathological conditions. Evolocumab, an inhibitor of proprotein convertase subtilisin/kexin type 9 (PCSK9), has recently been approved for treatment of hypercholesterolemia. This study aimed to investigate the effect of evolocumab on angiogenesis in human umbilical vein endothelial cells (HUVECs). Cell proliferation and migration were evaluated using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and Transwell methods. In vitro angiogenesis was assessed by tube formation assay. Vascular endothelial growth factor (VEGF) secretion by HUVECs was also determined using an enzyme-linked immunosorbent assay kit. Evolocumab significantly increased HUVECs viability at 100 μg/mL. Significant enhancement in cell migration, and mean tubules length and size was observed at the concentrations of 10 and 100 μg/mL and also in mean number of junctions at the concentration of 100 μg/mL. Administration of evolocumab at the concentration of 10 μg/mL increased VEGF release into supernatants of HUVECs. Findings of this investigation provided in vitro evidence for pro-angiogenic activity of evolocumab through promoting cell proliferation, migration, tubulogenesis, and VEGF secretion in HUVECs.

scholarly journals Polymer-Salt Aqueous Two-Phase System (ATPS) Micro-Droplets for Cell Encapsulation

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Mohammad Mastiani ◽  
Negar Firoozi ◽  
Nicholas Petrozzi ◽  
Seokju Seo ◽  
Myeongsub Kim
Keyword(s):  
Umbilical Vein ◽  
Cell Encapsulation ◽  
Salt System ◽  
Great Promise ◽  
Phase System ◽  
Two Phase ◽  
Aqueous Two Phase System ◽  
Wide Range ◽  
A Cell ◽  
Umbilical Vein Endothelial Cells

Abstract Biosample encapsulation is a critical step in a wide range of biomedical and bioengineering applications. Aqueous two-phase system (ATPS) droplets have been recently introduced and showed a great promise to the biological separation and encapsulation due to their excellent biocompatibility. This study shows for the first time the passive generation of salt-based ATPS microdroplets and their biocompatibility test. We used two ATPS including polymer/polymer (polyethylene glycol (PEG)/dextran (DEX)) and polymer/salt (PEG/Magnesium sulfate) for droplet generation in a flow-focusing geometry. Droplet morphologies and monodispersity in both systems are studied. The PEG/salt system showed an excellent capability of uniform droplet formation with a wide range of sizes (20–60 μm) which makes it a suitable candidate for encapsulation of biological samples. Therefore, we examined the potential application of the PEG/salt system for encapsulating human umbilical vein endothelial cells (HUVECs). A cell viability test was conducted on MgSO4 solutions at various concentrations and our results showed an adequate cell survival. The findings of this research suggest that the polymer/salt ATPS could be a biocompatible all-aqueous platform for cell encapsulation.

scholarly journals Crack channelling mechanisms in brittle coating systems under moisture or temperature gradients

2020 ◽  
Vol 225 (1) ◽  
pp. 1-30
Author(s):  
E. Bosco ◽  
A. S. J. Suiker ◽  
N. A. Fleck
Keyword(s):  
Elastic Modulus ◽  
Failure Mechanism ◽  
Paint Layer ◽  
Substrate Thickness ◽  
Indoor Climate ◽  
Brittle Coating ◽  
Climate Fluctuations ◽  
Art Objects ◽  
Wide Range ◽  
Moisture State

AbstractCrack channelling is predicted in a brittle coating-substrate system that is subjected to a moisture or temperature gradient in the thickness direction. Competing failure scenarios are identified, and are distinguished by the degree to which the coating-substrate interface delaminates, and whether this delamination is finite or unlimited in nature. Failure mechanism maps are constructed, and illustrate the sensitivity of the active crack channelling mechanism and associated channelling stress to the ratio of coating toughness to interfacial toughness, to the mismatch in elastic modulus and to the mismatch in coefficient of hygral or thermal expansion. The effect of the ratio of coating to substrate thickness upon the failure mechanism and channelling stress is also explored. Closed-form expressions for the steady-state delamination stress are derived, and are used to determine the transition value of moisture state that leads to unlimited delamination. Although the results are applicable to coating-substrate systems in a wide range of applications, the study focusses on the prediction of cracking in historical paintings due to indoor climate fluctuations, with the objective of helping museums developing strategies for the preservation of art objects. For this specific application, crack channelling with delamination needs to be avoided under all circumstances, as it may induce flaking of paint material. In historical paintings, the substrate thickness is typically more than ten times larger than the thickness of the paint layer; for such a system, the failure maps constructed from the numerical simulations indicate that paint delamination is absent if the delamination toughness is larger than approximately half of the mode I toughness of the paint layer. Further, the transition between crack channelling with and without delamination appears to be relatively insensitive to the mismatch in the elastic modulus of the substrate and paint layer. The failure maps developed in this work may provide a useful tool for museum conservators to identify the allowable indoor humidity and temperature fluctuations for which crack channelling with delamination is prevented in historical paintings.

MP81-18 EFFECTS OF SEX HORMONES ON CELL PROLIFERATION IN HUMAN UMBILICAL VEIN ENDOTHELIAL CELLS

2017 ◽  
Vol 197 (4S) ◽  
Author(s):  
Yasumasa Miyazaki ◽  
Takeo Kosaka ◽  
Eiji Kikuchi ◽  
Akira Miyajima ◽  
Mototsugu Oya
Keyword(s):  
Cell Proliferation ◽  
Endothelial Cells ◽  
Sex Hormones ◽  
Umbilical Vein ◽  
Human Umbilical Vein ◽  
Umbilical Vein Endothelial Cells

scholarly journals Modular operation of microfluidic chips for highly parallelized cell culture and liquid dosing via a fluidic circuit board

2020 ◽  
Vol 6 (1) ◽  
Author(s):  
A. R. Vollertsen ◽  
D. de Boer ◽  
S. Dekker ◽  
B. A. M. Wesselink ◽  
R. Haverkate ◽  
...  
Keyword(s):  
Cell Culture ◽  
Large Scale ◽  
Dynamic Range ◽  
Umbilical Vein ◽  
Building Blocks ◽  
High Dynamic Range ◽  
Microfluidic System ◽  
Circuit Board ◽  
Microfluidic Chips ◽  
Umbilical Vein Endothelial Cells

AbstractMicrofluidic systems enable automated and highly parallelized cell culture with low volumes and defined liquid dosing. To achieve this, systems typically integrate all functions into a single, monolithic device as a “one size fits all” solution. However, this approach limits the end users’ (re)design flexibility and complicates the addition of new functions to the system. To address this challenge, we propose and demonstrate a modular and standardized plug-and-play fluidic circuit board (FCB) for operating microfluidic building blocks (MFBBs), whereby both the FCB and the MFBBs contain integrated valves. A single FCB can parallelize up to three MFBBs of the same design or operate MFBBs with entirely different architectures. The operation of the MFBBs through the FCB is fully automated and does not incur the cost of an extra external footprint. We use this modular platform to control three microfluidic large-scale integration (mLSI) MFBBs, each of which features 64 microchambers suitable for cell culturing with high spatiotemporal control. We show as a proof of principle that we can culture human umbilical vein endothelial cells (HUVECs) for multiple days in the chambers of this MFBB. Moreover, we also use the same FCB to control an MFBB for liquid dosing with a high dynamic range. Our results demonstrate that MFBBs with different designs can be controlled and combined on a single FCB. Our novel modular approach to operating an automated microfluidic system for parallelized cell culture will enable greater experimental flexibility and facilitate the cooperation of different chips from different labs.

Observations on Biological Effects of Carbon-13, Based on the Effects of 13C-Testosterone on Growth of Human Osteoblasts, Human Aortic Endothelial Cells, and Human Umbilical Vein Endothelial Cells in Vitro

2021 ◽  
Author(s):  
Mengqi Zhang ◽  
Wenning Yang ◽  
Xinchen Wu ◽  
Tengfei Zhang
Keyword(s):  
Cell Proliferation ◽  
Endothelial Cells ◽  
Isotope Effect ◽  
Umbilical Vein ◽  
Biological Effects ◽  
Bioactive Compound ◽  
Human Osteoblasts ◽  
Aortic Endothelial Cells ◽  
Umbilical Vein Endothelial Cells

Abstract Despite the increasing knowledge of biological isotope effect, comprehensive understanding of heavy isotope effect in the biological contexts has remained far less than expectation. The present study investigated the carbon isotope effect of 13C enriched testosterone on human cells. It was among the rare studies on carbon isotope effect of bioactive compound. Human osteoblasts, human aortic endothelial cells, and human umbilical vein endothelial cells were cultured in vitro and treated with testosterone and 13C enriched testosterone (13C/12C:6.7%). The impacts of physiological to pharmacological concentrations (10-10-10-5mol/L) of the bioactive compound were taken into account. The cell proliferation activities were measured using MTS assay. The levels of alkaline phosphatase and osteocalcin in osteoblasts were tested. Our results established that 13C enriched testosterone exhibited different biological effects from testosterone. At the concentrations of 10-10mol/L and 10-5mol/L, there were significant differences in prompting cell proliferation between testosterone and 13C enriched testosterone. At physiological concentrations, testosterone prompted proliferations of the three kinds of cells; whereas, 13C enriched testosterone did not prompt the cell proliferation, and its effects were not concentration dependent. At supraphysiological concentration (10-5mol/L), testosterone had the trend of inhibiting cell growth; whereas, 13C enriched testosterone had the trend of prompting cell growth. 13C enriched testosterone significantly enhanced osteocalcin secretion in human osteoblasts at supraphysiological concentration. These findings challenged the common view of growth retardation effect of heavy isotope, which imply that biological isotope effects are worthy of further study. The potential applications of 13C enriched compound were discussed.

scholarly journals Regulation of endothelial proliferation by the renin–angiotensin system in human umbilical vein endothelial cells

Reproduction ◽  
2008 ◽  
Vol 136 (1) ◽  
pp. 125-130 ◽  
Author(s):  
D Herr ◽  
M Rodewald ◽  
H M Fraser ◽  
G Hack ◽  
R Konrad ◽  
...  
Keyword(s):  
Gene Expression ◽  
Cell Proliferation ◽  
Endothelial Cells ◽  
Angiotensin Ii ◽  
Umbilical Vein ◽  
Renin Angiotensin System ◽  
Angiotensin System ◽  
Human Umbilical Vein ◽  
Renin Angiotensin ◽  
Umbilical Vein Endothelial Cells

This study was performed in order to evaluate the role of angiotensin II in physiological angiogenesis. Human umbilical vein endothelial cells (HUVEC) were stained for angiotensin II type 1 receptor (AGTR1) immunocytochemically and for gene expression of renin–angiotensin system (RAS) components. The regulation of the angiogenesis-associated genes vascular endothelial growth factor (VEGF) and angiopoietins (ANGPT1andANGPT2) were studied using quantitative RT-PCR. Furthermore, we examined the effect of angiotensin II on the proliferation of HUVEC using Ki-67 as well as BrdU immunocytochemistry and investigated whether the administration of the AGTR1 blocker candesartan or the VEGF antagonist FLT1-Fc could suppress the observed angiotensin II-dependent proangiogenic effect. AGTR1 was expressed in HUVEC and the administration of angiotensin II significantly increased the gene expression ofVEGFand decreased the gene expression ofANGPT1. Since the expression ofANGPT2was not affected significantly the ratio of ANGPT1/ANGPT2 was decreased. In addition, a significantly increased endothelial cell proliferation was observed after stimulation with angiotensin II, which was suppressed by the simultaneous administration of candesartan or the VEGF antagonist FLT1-Fc. These results indicate the potential capacity of angiotensin II in influencing angiogenesis by the regulation of angiogenesis-associated genes via AGTR1. Since VEGF blockade opposed the effect of angiotensin II on cell proliferation, it is hypothesised that VEGF mediates the angiotensin II-dependent effect in concert with the changes in angiopoietin expression. This is the first report of the RAS on the regulation of angiogenesis-associated genes in physiology.

Sign in / Sign up

Export Citation Format

Share Document